The present invention relates to a method for determining sodium concentration in alcohol, which is effectively usable for speedy and accurate determination of sodium concentration in an alcoholic washing fluid used in the removal of sodium adherent to the sodium-related equipments or the like of a fast breeder reactor using liquid sodium as a coolant.
Sodium removal by alcohol is widely employed in Japan and abroad, because it is considered that the reactions occurring in this removal are so mild that the structural material of sodium-related equipments is little affected by the removal.
In the above sodium removal, determination of sodium concentration in alcohol is necessary for grasping the progress of the removal or judging the completion of the removal. Up to this time, the quantity of sodium dissolved in alcohol has been determined by neutralization titration. According to this method, however, it took about one hour to conduct one analyzing run, so that the sampling had to be conducted at intervals of 1 to 2 hours. Accordingly, it was impossible to determine or monitor the progress of the removal continuously by this method. The neutralization titration therefore had the problem that the timing of discontinuing the removal or a suitable timing of exchanging the alcoholic washing fluid could not be determined exactly.
Although the determination of sodium concentration in alcohol has been conducted also by measuring the conductivity of alcohol, the characteristics, quantitativeness or applicability of this method has not been elucidated at all, so that it was difficult to accurately determine sodium concentration in alcohol on the basis of the conductivity of alcohol. Accordingly, the determination of sodium concentration in alcohol on the basis of the conductivity has been employed merely as auxiliary means for determining the progress of sodium removal.